Sorry about messing that one up . I havent seen a two spd axle in a 1 ton but have in a 1 1/2 ton . Some thing you maght try to find a 5 spd O/D trans from a larger truck . once you get past shift pattern is OK .

I haven't seen any 2 speeds for a 1 ton..Everybody I know uses a Spicer auxiliary transmission..I put one in my F-600..A buddy of mine has one in a 1970 C-20 Camper Special pick-up truck powered with a Detroit 3-53..My F-600 picked up about 8 mph at 2500 rpms..I then went to taller tires and picked up another 4 to 5 mph.